I too built electronic projects as a kid. I've recently been getting back into it by slowly accumulating my 'bench' gear and I've bought an Arduino kit to start messing about building stuff while dusting off my (very!) dusty coding skills.
I've just built the LED flasher on breadboard & working as it should. My IC's are CD4047BD made by HLF. I did a diode check (with black lead on pin7). Like you, I got a reading (1.8v) on pin 10, BUT I also got the same reading on pin 11. So my working chips are showing a difference with your non-working ones.
I learned electronics bij building Velleman kits and just by trying to repair things I did make the complete mixer they had in those days was a fun project
@@Dutch-linux you didn't say that . I cant read minds through the Internet. Knead dough with sound, intresting 🤔. Even i dont believe that your's kitchen big enough to contain a 24 channel mixer. 🤪🤭🤭. How big is your oven 😳??
@@Lightrunner. Funnily enough in Spanish 'Mezclador' which is the translation of English 'mixer' also means something you use in a kitchen to make smoothies ans similar uses. What I would call a mixer (like a DJ would use) the Spanish, or at least Canarios, call that 'Mesa de Sonido' or something like that which translates like a Sound Table or Soundboard 😉
Surface mounted digital electronics soldered directly onto the PCB by robots turn most of us off. I found I could skip the PCB manufacture by stabbing thumb tacks into box corrugated cardboard or soft wood, and then use the tops of the metal thumbtacks to solder point to point wiring too like the old school vacuum radio manufacturers did. Wild, and it works.
Yeah I also started by hammering small nails into piece of wood. That was my 'pcb' then I soldered components and wires to it. To be honest soldering SMD is no more difficult than soldering through hole in most cases, in fact desoldering them is often easier. I think I proved that on this channel a few times at least. At least down to 0402 and SOIC/QFP. Soldering 0201 is fiddly but doable and QFN is also challenging at least at first.
I find using smd components easier these days, no need to keep turning the board over. I started with 1206 size so all my early PCBs use those, but now I use 0603 unless the component value means I have to go bigger. It makes for a smaller, neater layout.
I bought 3 amplifier Ic's in one hit from a seller on Aliexpress just recently. 2 chps had the numbers etched, and one had painted nubers (raised eyebrow). The painted chip was found to be a fake amongst the 2 good chips aftter comparing meter readings with a known good chip.
This could be a case of fake ICs but don't you think it is odd that they basically function as expected for 4047, just problems with the Q and /Q outputs. That would mean a similar chip would have been made which worked his way, and it is cheaper to remark them than sell the correct chip. Hmmmm 🤨
Pin 13 is driven directly by the oscillator, pins 10 and 11 are driven by a series of gates and flip-flops. There only needs to be a small manufacturing fault to leave the chip in this state. They may have been grabbed from the reject pile. It is possible that other functions, eg monostable mode, may work correctly so they may have been put in a box labeled with the working mode. The person who took them from that box probably wouldn't know the difference.
You could try the circuit at 3 or 5 volts. CMOS works from 3 ro 15 while TTL is 5 V. It might work on a lower voltage. The chips are late stage kitchen remodels -- counter fitted 😅😅 Juat look at the TI logo.
Good idea, we can try this on the followup video, FYI the pcbway prject was running at 12V and the LED flasher I built on the breadboard was running at 9V
You could try rubbing the chips with IPA or acetone. If they're repainted (which has been known to happen), the paint might come off. If nothing happens, you won't know if the chips are good. But if the paint comes off, you'll know that they're fake. And it's relatively easy to test.
Well from what the LEDs were doing on the breadboard LED flasher, which did not use MOSFETs and what my scope showed me on the Inverter PCB, both MOSFETs were definitely not on at the same time.
I learned electronics as a kid in the way must people probably did in those days, by mucking around with stuff! There were also hobby magazines and one could find old radios and TV’s on the dump back then. My mum realised that electronics was probably going to be the future and bought me an electronics set for my 9th Birthday( Denshi block. Who remembers them!) and 4 decades later I’m still mucking about! (
The circuit you use is wrong - at 6:20 we see that both the ASTABLE and ~ASTABLE inputs are connected to the supply. Meanwhile, the datasheet reads: "Astable operation is enabled by a high level on the ASTABLE input or a LOW level on the ~ASTABLE input, or both". Try reconnecting the ~ASTABLE input to GND.
Ok, so just the description in the datasheet itslef is inconsistent... Why would they make a chip that has two of the same inputs, just one negated, and then tie them both to the same signal? Where is the logic in that (pun intended)
@maks886 *Astable operation is enabled by a high level on the ASTABLE input or a LOW level on the ~ASTABLE input, or both* Try reconnecting the ~ASTABLE input to GND. Yes I also saw that in the datasheet so let's try it anyway just to see what happens. As @manticore1960 says the circuit is correct according to the table in the datasheet
Hello Richard it looks like the chips are fake or faulty. Ik presume that you tested alle of your available chips? An ic-tester could be an option, if you have one. Any scrapboards with a cd4047 on board? Testing without the LED's to check the wavevorm? Maybe the drawn current gives a clue. I am out of options. I will be watching for the solution. Best regards, Henk
Hi. If they are fake then what are they, as the basically work correctly apart from Q and /Q outputs. I do have three different logic IC testers here, plus a fourth one I'm building. Let's try them and compare them on the followup next week, it should be a fun video to make. Thanks for the suggestions
It seems to only want to work in monostable mode. I have to agree with a lot of the comments about fake/reject chips. If you buy more from a different seller on AliExpress you might still end up with the same problem. He might still source them from the same place as the first seller. As an experiment, I ordered 2 types of IC's from AE a few years ago. Both types failed miserably, all 20 of them. They "worked" to an extent, but were way out of specification. I would try a reputable supplier. I know it will cost a lot more than AE, but you will know they are genuine.
Not sure what you mean by monostable mode. The chip is oscillating freely so that means it is astable yeah? I will order some more, I also have plenty of suggestions to try next week in a followup.
@@LearnElectronicsRepair The oscillator is running, but the Q & BARQ outputs (pins 10 & 11)are acting as a monostable. One output is high at switch on, then permanently goes low. It only has one stable state.
btw...I'm not suggesting that the circuit is wired wrong. There's nothing wrong with it. That astable circuit has been used many times successfully over the years.
@@Manticore1960 Ahh I see 🙂 Yeah there are four signals that control the frequency divider built into the 4047, which in turn drives the Q and /Q outputs. This is where the problem seems to be and is something to explore in part two. It will be a good example of how to read understand datasheets for beginners too. For others interested check out this datasheet, page 2. It shows the block diagram of the 4047 and the function pin connections table pdf1.alldatasheet.com/datasheet-pdf/view/26874/TI/CD4047.html
Yeah polyester. But the oscillator does work as expected (see pin 13) and anyway the other circuit I built on the breadboard uses an electrolytic and also has exactly the same problem Odd isn't it 😉
@@LearnElectronicsRepair Electrolytic capacitors are polarized and the spec sheet calls for non polarized so this might be an issue. Hey I'm only a carpenter but hopefully learning lots from having to problem solve..
Also pin rows 18-21 look rough. If those guys could talk they may say replace me. I think once a new batch come in everything will check out. Even on that screaming breadboard. Lol. Great video title.
I don't have a ESD safe matt and to date haven't had any problems, Maybe the chip needs decoupling as your on bread board or it's a 'sink/source current' problem and you need to pull them up or down or your supply isn't providing enough current or your timing cap is wrong or retrigger is set wrong...or.....They are fake !.....cheers.
Well the chips behave the same way in the original project and the breadboard which is a different circuit. There is no mention of pull up or pull down resistors being needed, also the pin 13 osc output works and it looks the same as Q and /Q outputs at least to a multimeter in diode mode. if they are fake, then what are they? The appear to be a chip that works like a 4047 should apart from this problem and it would have to be economically viable to remark the mas fakes rather than just sell them as what they are.... hmmmm
Can you buy new chips from a reputable seller (e.g., Mouser, Digikey) and help us viewers to understand this mystery? You can post the end conclusion in your comments. Thanks.
@@alessandrodonascimentovarg24 Yes I will get some chips from another supplier. I'm also going to try various suggestions on these comments so expect a followup after the weekend
Only reason I have an ESD mat on my desk is so that in the winter here in Canada when I get up out of my chair and touch the light switch I don't get zapped with static electricity. Humdity here during winter can get down to 20% at times.
You don't need sites to do that, just use the colour code values. 220 ohm 5 band is red red black black. Yeah I know that is 4 bands. The fifth band is the tolerance For 22 ohm 5 band you would have red red black gold (plus a tolerance band). We were able to read resistor colour codes decades before we had the internet you know, strange though that may sound 😅
@@LearnElectronicsRepair…for good measure on the mosfet gates else they may not turn off. Did you notice how the breadboard version started to oscillate when you pulled the power? Is your PSU free of ripple?
@@teslasapple This could be the cause of the problem... as I mentioned towards the end of the video I thought the problem could be related to capacitors 😉
Nope not sure, though it is a strange failure mode don't you think? There would have to be some other type of chip that worked in the way I found with both these circuits, and was remarked.
*Keep the suggestions coming guys and we can try them all on a followup next week* 🙂
I too built electronic projects as a kid. I've recently been getting back into it by slowly accumulating my 'bench' gear and I've bought an Arduino kit to start messing about building stuff while dusting off my (very!) dusty coding skills.
I've just built the LED flasher on breadboard & working as it should. My IC's are CD4047BD made by HLF. I did a diode check (with black lead on pin7). Like you, I got a reading (1.8v) on pin 10, BUT I also got the same reading on pin 11. So my working chips are showing a difference with your non-working ones.
I learned electronics bij building Velleman kits and just by trying to repair things I did make the complete mixer they had in those days was a fun project
Hey super, with your repaired mixer you can baking bread now .
🤣🤣
@@Lightrunner. what are you on about dude ?? it was a 24 channnel professional audio mixer project they had !! you may need to eat more bread !!!
@@Dutch-linux you didn't say that . I cant read minds through the Internet. Knead dough with sound, intresting 🤔.
Even i dont believe that your's kitchen big enough to contain a 24 channel mixer. 🤪🤭🤭. How big is your oven 😳??
@@Lightrunner. Funnily enough in Spanish 'Mezclador' which is the translation of English 'mixer' also means something you use in a kitchen to make smoothies ans similar uses. What I would call a mixer (like a DJ would use) the Spanish, or at least Canarios, call that 'Mesa de Sonido' or something like that which translates like a Sound Table or Soundboard 😉
Good to see someone else with a half melted breadboard!
Hehe yeah that happened on one of the livestreams @theelectronicschannel I consider it a badge of honour LOL
yeah, dont we all have those marks on our breadboards. If you dont, then you are doing something wrong... wink wink.
Let us newbs know whether to steer clear of AliX. Thanks for great information and training.
We will find out in the next part
Thank you for your efforts, sir Richard.
You need more videos like this and use the scope to see what and how things work!!!!!!
Surface mounted digital electronics soldered directly onto the PCB by robots turn most of us off.
I found I could skip the PCB manufacture by stabbing thumb tacks into box corrugated cardboard or soft wood, and then use the tops of the metal thumbtacks to solder point to point wiring too like the old school vacuum radio manufacturers did. Wild, and it works.
Yeah I also started by hammering small nails into piece of wood. That was my 'pcb' then I soldered components and wires to it. To be honest soldering SMD is no more difficult than soldering through hole in most cases, in fact desoldering them is often easier. I think I proved that on this channel a few times at least. At least down to 0402 and SOIC/QFP. Soldering 0201 is fiddly but doable and QFN is also challenging at least at first.
I find using smd components easier these days, no need to keep turning the board over. I started with 1206 size so all my early PCBs use those, but now I use 0603 unless the component value means I have to go bigger. It makes for a smaller, neater layout.
I bought 3 amplifier Ic's in one hit from a seller on Aliexpress just recently. 2 chps had the numbers etched, and one had painted nubers (raised eyebrow). The painted chip was found to be a fake amongst the 2 good chips aftter comparing meter readings with a known good chip.
This could be a case of fake ICs but don't you think it is odd that they basically function as expected for 4047, just problems with the Q and /Q outputs. That would mean a similar chip would have been made which worked his way, and it is cheaper to remark them than sell the correct chip. Hmmmm 🤨
Pin 13 is driven directly by the oscillator, pins 10 and 11 are driven by a series of gates and flip-flops. There only needs to be a small manufacturing fault to leave the chip in this state.
They may have been grabbed from the reject pile. It is possible that other functions, eg monostable mode, may work correctly so they may have been put in a box labeled with the working mode. The person who took them from that box probably wouldn't know the difference.
You could try the circuit at 3 or 5 volts. CMOS works from 3 ro 15 while TTL is 5 V. It might work on a lower voltage. The chips are late stage kitchen remodels -- counter fitted 😅😅 Juat look at the TI logo.
Good idea, we can try this on the followup video, FYI the pcbway prject was running at 12V and the LED flasher I built on the breadboard was running at 9V
Looks like you need to adjust and calibrate the trimmer capacitor in your scope probe to get that square wave flattened 😁
You could try rubbing the chips with IPA or acetone. If they're repainted (which has been known to happen), the paint might come off. If nothing happens, you won't know if the chips are good. But if the paint comes off, you'll know that they're fake. And it's relatively easy to test.
Let's try this in the followup next week
Try pulling out one of the mosfets, maybe the gate on’s are overlapping so both mosfets are on at the same time.
Well from what the LEDs were doing on the breadboard LED flasher, which did not use MOSFETs and what my scope showed me on the Inverter PCB, both MOSFETs were definitely not on at the same time.
I learned electronics as a kid in the way must people probably did in those days, by mucking around with stuff! There were also hobby magazines and one could find old radios and TV’s on the dump back then. My mum realised that electronics was probably going to be the future and bought me an electronics set for my 9th Birthday( Denshi block. Who remembers them!) and 4 decades later I’m still mucking about! (
The circuit you use is wrong - at 6:20 we see that both the ASTABLE and ~ASTABLE inputs are connected to the supply. Meanwhile, the datasheet reads: "Astable operation is enabled by a high level on the ASTABLE input or a LOW level on the ~ASTABLE input, or both". Try reconnecting the ~ASTABLE input to GND.
The circuit is correct according to the table in the datasheet. Every circuit on the internet has those 2 pins tied to supply.
Ok, so just the description in the datasheet itslef is inconsistent... Why would they make a chip that has two of the same inputs, just one negated, and then tie them both to the same signal? Where is the logic in that (pun intended)
It is all to do with what triggers the change, monostable, retriggerable, astable, resettable etc. But I agree, it is very misleading.
@maks886 *Astable operation is enabled by a high level on the ASTABLE input or a LOW level on the ~ASTABLE input, or both* Try reconnecting the ~ASTABLE input to GND. Yes I also saw that in the datasheet so let's try it anyway just to see what happens. As @manticore1960 says the circuit is correct according to the table in the datasheet
Hello Richard it looks like the chips are fake or faulty. Ik presume that you tested alle of your available chips? An ic-tester could be an option, if you have one. Any scrapboards with a cd4047 on board? Testing without the LED's to check the wavevorm? Maybe the drawn current gives a clue. I am out of options. I will be watching for the solution. Best regards, Henk
Hi. If they are fake then what are they, as the basically work correctly apart from Q and /Q outputs. I do have three different logic IC testers here, plus a fourth one I'm building. Let's try them and compare them on the followup next week, it should be a fun video to make. Thanks for the suggestions
Maybe they're not fake, just defective chips that were manufactured one after the other.
@@markanderson2904 That makes more sense than them being fake. To me at least.
OH I didn't test all the chips (ten of them) only the four I showed in this video
@@LearnElectronicsRepair Maybe one last tip clean the contacts of the chips. Sometimes the get corroded. See you next week. best regards, Henk
It seems to only want to work in monostable mode. I have to agree with a lot of the comments about fake/reject chips. If you buy more from a different seller on AliExpress you might still end up with the same problem. He might still source them from the same place as the first seller. As an experiment, I ordered 2 types of IC's from AE a few years ago. Both types failed miserably, all 20 of them. They "worked" to an extent, but were way out of specification. I would try a reputable supplier. I know it will cost a lot more than AE, but you will know they are genuine.
Not sure what you mean by monostable mode. The chip is oscillating freely so that means it is astable yeah? I will order some more, I also have plenty of suggestions to try next week in a followup.
@@LearnElectronicsRepair The oscillator is running, but the Q & BARQ outputs (pins 10 & 11)are acting as a monostable. One output is high at switch on, then permanently goes low. It only has one stable state.
I'm not 100% certain, but I think the oscillator runs all the time, whether it's in monostable or astable mode.
btw...I'm not suggesting that the circuit is wired wrong. There's nothing wrong with it. That astable circuit has been used many times successfully over the years.
@@Manticore1960 Ahh I see 🙂 Yeah there are four signals that control the frequency divider built into the 4047, which in turn drives the Q and /Q outputs. This is where the problem seems to be and is something to explore in part two. It will be a good example of how to read understand datasheets for beginners too.
For others interested check out this datasheet, page 2. It shows the block diagram of the 4047 and the function pin connections table
pdf1.alldatasheet.com/datasheet-pdf/view/26874/TI/CD4047.html
Is that a polyester capacitor ? Higher losses than the ceramic in the example.
Yeah polyester. But the oscillator does work as expected (see pin 13) and anyway the other circuit I built on the breadboard uses an electrolytic and also has exactly the same problem Odd isn't it 😉
@@LearnElectronicsRepair Electrolytic capacitors are polarized and the spec sheet calls for non polarized so this might be an issue. Hey I'm only a carpenter but hopefully learning lots from having to problem solve..
Also pin rows 18-21 look rough. If those guys could talk they may say replace me. I think once a new batch come in everything will check out. Even on that screaming breadboard. Lol. Great video title.
Cheers. The breadboard got fried on one of the live streams @theelectronicschannel I consider the burned part to be a badge of honour lol
@@LearnElectronicsRepair I would too, tell you the truth. I have a set of Alligator clips I keep for the same reason.
I don't have an anti static mat bc I juat never got one and now I'm really poor.
I don't have a ESD safe matt and to date haven't had any problems, Maybe the chip needs decoupling as your on bread board or it's a 'sink/source current' problem and you need to pull them up or down or your supply isn't providing enough current or your timing cap is wrong or retrigger is set wrong...or.....They are fake !.....cheers.
Well the chips behave the same way in the original project and the breadboard which is a different circuit. There is no mention of pull up or pull down resistors being needed, also the pin 13 osc output works and it looks the same as Q and /Q outputs at least to a multimeter in diode mode. if they are fake, then what are they? The appear to be a chip that works like a 4047 should apart from this problem and it would have to be economically viable to remark the mas fakes rather than just sell them as what they are.... hmmmm
Can you buy new chips from a reputable seller (e.g., Mouser, Digikey) and help us viewers to understand this mystery? You can post the end conclusion in your comments. Thanks.
@@LearnElectronicsRepair hmmmm indeed...we shall see :)
@@alessandrodonascimentovarg24 Yes I will get some chips from another supplier. I'm also going to try various suggestions on these comments so expect a followup after the weekend
Only reason I have an ESD mat on my desk is so that in the winter here in Canada when I get up out of my chair and touch the light switch I don't get zapped with static electricity. Humdity here during winter can get down to 20% at times.
Heya, I have a hart feeling that all those chips are faulty, but I don't daire to say what it is
It's not about ordering, it's about designing PCB layout, SMD, etc
I did a couple of videos on that topic, would you like more?
Without having looked into the datasheet of this chip: is it correct to have both ASTABLE and -ASTABLE pulled up to Vpp?
...sorry, should have read the comments before writing
I tried various sites to get the colours for a 22 ohm and/or a 220 ohm 5 band. I gave up.
You don't need sites to do that, just use the colour code values. 220 ohm 5 band is red red black black. Yeah I know that is 4 bands. The fifth band is the tolerance
For 22 ohm 5 band you would have red red black gold (plus a tolerance band). We were able to read resistor colour codes decades before we had the internet you know, strange though that may sound 😅
I have just had three totally Naff chips from China. I would understand one bad not all.
test the chip in the programer it has a test function
We can try this in the next part
I think it must be the circuit press incorrect? Steve b
Can you elaborate?
You need pull downs on the gates
Which ones? Inputs or Outputs
@@LearnElectronicsRepair…for good measure on the mosfet gates else they may not turn off. Did you notice how the breadboard version started to oscillate when you pulled the power? Is your PSU free of ripple?
@@teslasapple This could be the cause of the problem... as I mentioned towards the end of the video I thought the problem could be related to capacitors 😉
Heathkit
Soo, you're not questioning the board?
Sorry, just watched as you breadboarded it...
@@DogsLife12 Yep. And I breadboarded a different circuit (LED flasher) and I have the same faulty behaviour, more or less
are you sure you do not have fake chips ???
Nope not sure, though it is a strange failure mode don't you think? There would have to be some other type of chip that worked in the way I found with both these circuits, and was remarked.
@@LearnElectronicsRepair I know ali is cheap but there is a very high risk of fake chips there .. better get it from mouser or digikey
Those are not 220 ohm resistors, those are 22 ohm resistors!
they are 5 band not 4.
@@fableblue2010oops, just watched it again, you're absolutely right. Sorry! 😅
@@Northern-Rambler No worries,m it happens 🙂
Another PCBWay project from Easyone. Hmm, not so easy either.
However we all learn a great deal from Easyone's projects so thanks to the original author and PCBWay for providing is such useful learning tools 🙂